Hi Liz

Welcome to RM forum. Matt was being pretty modest in promoting ReefMaster as a tool for you. I'd like to comment on RM as a user. I have been mapping coastlines for 15 years here in New Zealand and used many software tools in that time. RM is now my main tool as the go between the sounder and ArcGIS work. One thing Reefmaster does for you is it will very quickly convert line depth data into extrapolated 100% coverage, allowing you to generate contour lines of your choice. It integrates this process with a shoreline, which you can bring in to RM via a shapefile from your GIS. It gets better, once you get this far you can export from RM a GIS compatible 'grid' file. Once you have this in your GIS the world is your oyster because you can go straight to 3D work, make hillshade, contour layers etc. One other function in RM which is very useful is you can do your tide level adjustment easily, so that if you need to all the mapping layers and data you produce are tide adjusted. Assuming here you are working in salty water. So Liz you won't regret purchasing RM it is a great tool for integration with ArcGIS.

Liz you mentioned mapping obstructions etc. From what you have said it seems you are heading towards making side scan layers as well, which is now possible on most of the Lowrance and Humminbird machines. RM's capability to work with SS data is also excellent. There is some good expertise on working with SS checking in frequently with this forum, so suggest you start a thread at some point about your project and ask the questions as they arise.

Have fun.............................................................

You can also use NMEA 0183 external GPS and Heading sensors ..... NMEA 2000 is ridiculously expensive unless you are tying half a dozen devices together and besides the Elite 5 Ti doesn't support NMEA 2000 like the Elite 7 Ti, it only has NMEA 0183 I/O .... Heading Sensors need to be mounted away from magnetic fields which is why you don't find them built into any finder/plotters and if available are mounted externally to get them away from the high powered sonar signals inside the unit ..... Just like the new Bluetooth iPilots which have a separately mounted heading sensor. They mount it separately because of the high powered motor electronics in the base and because mounting it in the head with the GPS which is constantly moving would be pointless

I use an external GPS module with an active antenna placed right over my transducer otherwise you end up with an error that is the distance between the transducer and the finder times 2 .... While the error can be nulled out in software it's touchy and seems to need constant recalibration (Granted I haven't really tried it in Reefmaster since I moved to my current system of external GPS years ago when Dr Depth was the only depth survey solution)

To find the error I like to find a submerged log or a well defined ridge. First map across the log/ridge from one direction and save it and start a new track and map it from the exact opposite direction. In a perfect world the log/ridge will show up at the same coordinates but in the real world you will find them several meters apart and that will be roughly the distance between transducer and GPS antenna (finder) times 2 .....

BTW here is an excellent article on how to make a heading sensor using a smartphone as an example by an Applications Engineer from Freescale. Freescale is the manufacturer of the i.MX6 SoC Lowrance uses in the HDS and Elite Ti lines. The hardware is the easy part, it's translating all that math into computer code that's the hard part .... Math like this is why we invented computers in the first place and you aren't going to make a true heading sensor with tilt compensation with an 8 bit Arduino, more like a STM32 32 bit ARM processor GPS modules usually have an ARM processor inside doing all the hard work which makes them so easy to use.

Implementing a tilt compensated eCompass using accelerometer and magnetometer sensors

The Application Note with C# example code

I just bought a NEO-M8N module with external antenna (It's hard to find GPS modules with an external antenna port) which also has a magnetic compass IC built-in (Same Honeywell sensor the iPilot's use) but I'm not sure if I'll be using the compass part since it's not decoded (Just raw I2C sensor data) and is really for a drone flight controller which doesn't need tilt compensation like a boat since they fly essentially flat. Tilt might not be that important in a small boat as compared to sailing boats that are often tilted in 2 directions for long periods of time while the tilt in a small boat moving a few miles an hour is probably insignificant. The other problem with using it would be mounting my unit which is currently mounted on the side of the boat under the console which is part of the reason why I use external antennas in the first place. The module doesn't care about it's orientation, only the patch antenna does

lubby1010 wrote:
The Insight Map Creator (IMC) is free software but the Insight Planner software ($29.99) is good for seeing what your maps will look like on your finder without having to run out and plug an SD card into the unit. The map scrolling really sucks which is surprising since it is Fugawi 4.5 based which I've been using for Inland ENCs for the Mississippi River for years and it works great. However it does get the job done and also is a convenient place to archive maps and view them. I'm still trying to figure out how to get my yearly updated by the US Army Corps of Engineers Inland ENCs onto my Elite 7 Ti because they are better and more recent and accurate than the built in ones although the built-in ones aren't bad just not as good. The best part is they are completely free to download and last year started coming in KMZ and SHP formats as well as the tradition S-57. You can download the KMZ's and display them on Google Earth. However the S-57 format is much more detailed than the SHP and KMZ formats. Insight Planner will also display S-57 maps and sadly much better than it does AT5 maps .....

USACE Chart download page